The present invention relates to an insulation panel for cabinets containing air handling equipment, comprising a first housing section, a second housing section joined to the first housing section to form a space therebetween, and insulation material provided in said space.
Known air handling cabinets are manufactured by securing a number of such insulation panels on a framework to form a closed insulated cabinet. The air handling equipment to be accommodated in the cabinet is typically air dehumidification equipment but may comprise any air treatment devices that need to be thermally insolated from the enviroment. Air treatment generally involves heat exchange and therefore it is important that the cabinet is efficiently thermally insulated, in order to provide high thermal efficiency and low energy losses of the equipment. As to the insulation panel, its insulation quality is enhanced if thermal bridges are avoided between the first housing section, which may be exposed to the exterior side of the cabinet, and the second housing section, which may be exposed to the interior of the cabinet. The housing sections are typically made of bent metal sheet of high thermal conductivity.
It is known Ito fabricate the insulation panel by bonding abutting metal flanges of the first and second housing sections by the use of epoxy glue, which gives rise to the disadvantage that a relatively extensive thermal bridge is developed along the glue joint. Another disadvantage in this connection is that the epoxy glue emits unhealthy volatile substances to the enviroment as the glue cures. The emission of such substances is subject to ever increasing restrictions from the authorities, which may limit the production of the panels at the production site.
GE Patent Application No. 2280951 discloses an insulation panel of the above discussed type, in which the housing sections are inter-connected by welding. As a result, an undesirable thermal bridge is developed along the welded seam between the housing sections.
FR Patent No. 1358454 discloses an insulation panel, in which two housing sections are joined together by snap-in engagement means.
A problem common to all known insulation panels is that they are relatively expensive and labour-intensive to fabricate. Since a cabinet may be composed of several relatively large insulation panels, it is desirable to reduce the fabrication costs of each panel. Furthermore, they are deficient because of the existense of undesirable thermal bridges.
The object of the present invention is to provide an insulation panel, which is relatively inexpensive to fabricate and which has an improved insulation quality, as compared with prior art panels.
This object is obtained by the insulation panel presented initially, which is characterized in that the first housing section forms chamber and has an annular flange defining an opening into said chamber, that the second housing section has a circumferential side wall inserted through said opening into said chamber to form said space between the first an second housing sections, that snap-in engagement means are arranged on the circumferential side wall of the second housing section and adapted to snap engage with the flange of the first housing section, when said circumferential side wall is inserted through said opening into said chamber, to join the first and second housing sections to each other, the snap-in engagement means engaging said flange via a first gasket, and that the circumferential side wall of the second housing section abuts against the first housing section via a resilient second gasket, whereby the snap-in engagement means abut against said first gasket under some pressure to secure the first and second housing sections to each other.
The provision of the snap-in engagement means and said first and second gaskets enables a design of the panel which minimizes or even eliminates thermal bridges between the housing sections.
In a preferred embodiment of the invention, the first housing section comprises a planar first front wall and a circumferential side wall extending substantially perpendicular to the first front wall, the annular flange extending inwardly from the side wall in parallel with the planar first front wall, and the second housing section comprises a planar second front wall, the circumferential side wall of the second housing section extending substantially perpendicular to the planar second front wall.
Suitably, the circumferential side wall of the second housing section abuts against the first front wall of the first housing section via said resilient second gasket.
The gaskets are suitably made from a material having low thermal conductivity, which essentially eliminates thermal bridges between the first and second housing sections.
Preferably, the resilient second gasket is provided with an adhesive for adhering to the exterior front wall of the first housing section and the side wall of the second housing section, which makes the panel strong and distortion resistant.
The snap-in engagement means comprise a plurality of snap-in engagement members distributed around the circumferential side wall of the second housing section. Each snap-in engagement member preferably comprises a tab which extends outwardly from the side wall of the second housing section. As an alternative, each snap-in engagement member may comprise a protrusion which projects outwardly from the side wall of the second housing section.